Feature request: success message dialog

I used this script successfully on a fresh 15.0-RELEASE installation on VirtualBox, but the abrupt exit after the Select the users enabled for the graphical environment dialog made me think I'd accidentally selected Exit instead of Add.

It would have been helpful to have had a dialog with message box informing me that the KDE installation had been successful, the selected user(s) had been added, and that I can now restart.

Instead I ended up running the script again and finished up with the setup lines duplicated in my /etc/rc.conf. It would also be nice if the script only added these lines if it detected they were not already present!